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          <h1 class="post-title" itemprop="name headline">Flask构建可扩展的RESTful-API-4--理解WTForms并灵活改造她</h1>
        

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        <h1 id="4-1-重写WTForms"><a href="#4-1-重写WTForms" class="headerlink" title="4.1 重写WTForms"></a>4.1 重写WTForms</h1><h3 id="优化1"><a href="#优化1" class="headerlink" title="优化1"></a>优化1</h3><p>之前的代码，修改完成之后，已经修复了之前的缺陷，但是这样爆出了两个问题： 1.代码太啰嗦了，每个试图函数里，都需要这么写 2.ClientTypeError只是代表客户端类型异常，其他的参数校验不通过也抛出这个异常的话不合适</p>
<p>为了解决上面的问题，我们需要重写wtforms</p>
<h2 id="思路"><a href="#思路" class="headerlink" title="思路"></a>思路</h2><p>  继承原有的wtforms,重写validate_for_api，<strong>修改wtforms为抛出异常</strong><br>定义一个自定义BaseForm，让其他的Form来继承<br>app\validators\base.py<br><figure class="highlight plain"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br></pre></td><td class="code"><pre><span class="line">from wtforms import Form</span><br><span class="line">from app.libs.erro_code import ParameterException</span><br><span class="line"></span><br><span class="line">class BaseForm(Form):</span><br><span class="line">    def __init__(self, data):</span><br><span class="line">        super(BaseForm, self).__init__(data=data)   # 调用父类构造函数</span><br><span class="line"></span><br><span class="line">    def validate_for_api(self):</span><br><span class="line">        valid = super(BaseForm, self).validate()  # 调用父类的构造方法 # 验证是否通过</span><br><span class="line">        if not valid:   # 没通过</span><br><span class="line">            # 所有异常类信息在form errors 中 </span><br><span class="line">            raise ParameterException(msg=self.errors) #  抛出异常  # 公共的自定义异常类</span><br></pre></td></tr></table></figure></p>
<p>定义公共异常类</p>
<p>app\libs\erro_code.py<br><figure class="highlight plain"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br></pre></td><td class="code"><pre><span class="line">from app.libs.erro import APIException</span><br><span class="line"></span><br><span class="line">class ClientTypeErro(APIException):</span><br><span class="line">    code = 400</span><br><span class="line">    msg = &apos;client is invalid&apos;</span><br><span class="line">    erro_code = 1006</span><br><span class="line"></span><br><span class="line"></span><br><span class="line">class ParameterException(APIException):</span><br><span class="line">    code = 400</span><br><span class="line">    msg = &apos;invalid parameter&apos;</span><br><span class="line">    erro_code = 1000</span><br></pre></td></tr></table></figure></p>
<p>以后我们的试图函数就可以这样编写<br><figure class="highlight plain"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br><span class="line">16</span><br><span class="line">17</span><br><span class="line">18</span><br><span class="line">19</span><br><span class="line">20</span><br><span class="line">21</span><br><span class="line">22</span><br><span class="line">23</span><br><span class="line">24</span><br><span class="line">25</span><br><span class="line">26</span><br><span class="line">27</span><br><span class="line">28</span><br><span class="line">29</span><br><span class="line">30</span><br><span class="line">31</span><br><span class="line">32</span><br><span class="line">33</span><br><span class="line">34</span><br><span class="line">35</span><br><span class="line">36</span><br><span class="line">37</span><br><span class="line">38</span><br><span class="line">39</span><br><span class="line">40</span><br><span class="line">41</span><br><span class="line">42</span><br><span class="line">43</span><br><span class="line">44</span><br><span class="line">45</span><br><span class="line">46</span><br><span class="line">47</span><br><span class="line">48</span><br><span class="line">49</span><br></pre></td><td class="code"><pre><span class="line"></span><br><span class="line">from app.libs.redprint import Redprint</span><br><span class="line"></span><br><span class="line">from app.validators.forms import ClientForm,UserEmailForm</span><br><span class="line">from flask import request</span><br><span class="line">from app.libs.enums import ClientTypeEnum</span><br><span class="line">from app.models.user import User</span><br><span class="line"></span><br><span class="line"></span><br><span class="line"># from werkzeug.exceptions import HTTPException   #  异常</span><br><span class="line">from app.libs.erro_code import ClientTypeErro   # 导入自定义异常</span><br><span class="line"></span><br><span class="line">api = Redprint(&apos;client&apos;)  # 实例化一个Redprint</span><br><span class="line"></span><br><span class="line">@api.route(&apos;/register&apos;, methods = [&apos;POST&apos;] )  # 路由注册  # 因为这里把POST打成PSOT，导致不能使用POST访问，状态码405</span><br><span class="line">def create_client():                         </span><br><span class="line">    # 表单 - 一般网页  json - 一般移动端</span><br><span class="line">    # 注册 登录</span><br><span class="line">    # 参数 校验  接收参数</span><br><span class="line">    # WTForms 验证表单</span><br><span class="line"></span><br><span class="line">#用来接收json类型的参数</span><br><span class="line">    data = request.json</span><br><span class="line"># 关键字参数data是wtform中用来接收json参数的方法</span><br><span class="line">    form = ClientForm(data = data)  # data =   来接收json</span><br><span class="line">   </span><br><span class="line">    form.validate_for_api()</span><br><span class="line"># 替代switchcase-&#123;Enum_name:handle_func&#125;</span><br><span class="line">    promise = &#123;</span><br><span class="line">            ClientTypeEnum.USER_EMAIL: __register_user_by_email#,</span><br><span class="line">            # ClientTypeEnum.USER_MINA: __register_user_by_MINA   # 可在此处构建多种枚举类型</span><br><span class="line">        &#125;</span><br><span class="line">    promise[form.type.data]()</span><br><span class="line"></span><br><span class="line">    return &apos;sucess&apos;  #  暂时返回sucess</span><br><span class="line">#总 ↑</span><br><span class="line"></span><br><span class="line">#分 ↓</span><br><span class="line"></span><br><span class="line">def __register_user_by_email():</span><br><span class="line">    form = UserEmailForm(data=request.json)</span><br><span class="line">    if form.validate():</span><br><span class="line">        User.register_by_email(form.nickname.data,</span><br><span class="line">                               form.account.data,</span><br><span class="line">                               form.secret.data)</span><br><span class="line"></span><br><span class="line"></span><br><span class="line"># def __register_user_by_MINA():</span><br><span class="line">#     pass</span><br></pre></td></tr></table></figure></p>
<h3 id="优化2"><a href="#优化2" class="headerlink" title="优化2"></a>优化2</h3><p>目前我们每次都需要从request中取出json信息再传入到Form对象中，优化的思路是，直接传入request，在BaseForm中取出json<br>app\validators\base.py<br><figure class="highlight plain"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br></pre></td><td class="code"><pre><span class="line">from wtforms import Form</span><br><span class="line">from app.libs.erro_code import ParameterException</span><br><span class="line">from flask import request</span><br><span class="line"></span><br><span class="line">class BaseForm(Form):</span><br><span class="line">    # def __init__(self, data):</span><br><span class="line">    def __init__(self):</span><br><span class="line">        data = request.json</span><br><span class="line">        super(BaseForm, self).__init__(data=data)   # 调用父类构造函数</span><br><span class="line"></span><br><span class="line">    def validate_for_api(self):</span><br><span class="line">        valid = super(BaseForm, self).validate()  # 调用父类的构造方法 # 验证是否通过</span><br><span class="line">        if not valid:   # 没通过</span><br><span class="line">            # 所有异常类信息在form errors 中 </span><br><span class="line">            raise ParameterException(msg=self.errors) #  抛出异常  # 公共的自定义异常类</span><br></pre></td></tr></table></figure></p>
<h3 id="优化3"><a href="#优化3" class="headerlink" title="优化3"></a>优化3</h3><p>每次都需要实例化Form对象，再调用validate_for_api()方法，我们可以让validate_for_api方法返回一个self对象，这样就只需要一行代码就可以解决了<br>app\validators\base.py<br><figure class="highlight plain"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br><span class="line">16</span><br></pre></td><td class="code"><pre><span class="line">from wtforms import Form</span><br><span class="line">from app.libs.erro_code import ParameterException</span><br><span class="line">from flask import request</span><br><span class="line"></span><br><span class="line">class BaseForm(Form):</span><br><span class="line">    # def __init__(self, data):</span><br><span class="line">    def __init__(self):</span><br><span class="line">        data = request.json</span><br><span class="line">        super(BaseForm, self).__init__(data=data)   # 调用父类构造函数</span><br><span class="line"></span><br><span class="line">    def validate_for_api(self):</span><br><span class="line">        valid = super(BaseForm, self).validate()  # 调用父类的构造方法 # 验证是否通过</span><br><span class="line">        if not valid:   # 没通过</span><br><span class="line">            # 所有异常类信息在form errors 中 </span><br><span class="line">            raise ParameterException(msg=self.errors) #  抛出异常  # 公共的自定义异常类</span><br><span class="line">        return self</span><br></pre></td></tr></table></figure></p>
<h3 id="优化4"><a href="#优化4" class="headerlink" title="优化4"></a>优化4</h3><p>操作成功也需要返回json结构，且结构应该和异常的时候一样，所以我们可以定义一个Success继承APIException<br>app\libs\erro_code.py<br><figure class="highlight plain"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br><span class="line">16</span><br><span class="line">17</span><br><span class="line">18</span><br><span class="line">19</span><br><span class="line">20</span><br><span class="line">21</span><br><span class="line">22</span><br><span class="line">23</span><br><span class="line">24</span><br><span class="line">25</span><br><span class="line">26</span><br><span class="line">27</span><br><span class="line">28</span><br><span class="line">29</span><br><span class="line">30</span><br><span class="line">31</span><br><span class="line">32</span><br><span class="line">33</span><br><span class="line">34</span><br><span class="line">35</span><br><span class="line">36</span><br><span class="line">37</span><br></pre></td><td class="code"><pre><span class="line"></span><br><span class="line"># from werkzeug.exceptions import HTTPException</span><br><span class="line"># # 自定义异常类</span><br><span class="line"></span><br><span class="line"># class ClientTypeErro(HTTPException):</span><br><span class="line">#     code = 400</span><br><span class="line">#     description = (</span><br><span class="line">#         &apos;client is invalid&apos;</span><br><span class="line">#     )</span><br><span class="line">  </span><br><span class="line"></span><br><span class="line"># ↑ 不再继承HTTPException</span><br><span class="line"></span><br><span class="line"># ↓ 继承APIException</span><br><span class="line">from app.libs.erro import APIException</span><br><span class="line"></span><br><span class="line">class ClientTypeErro(APIException):</span><br><span class="line">    code = 400</span><br><span class="line">    msg = &apos;client is invalid&apos;</span><br><span class="line">    erro_code = 1006</span><br><span class="line"></span><br><span class="line"></span><br><span class="line">class ParameterException(APIException):</span><br><span class="line">    code = 400</span><br><span class="line">    msg = &apos;invalid parameter&apos;</span><br><span class="line">    erro_code = 1000</span><br><span class="line"></span><br><span class="line"># 将成功返回也当作一中 APIException，来优化代码</span><br><span class="line">class Success(APIException):</span><br><span class="line">    code = 201</span><br><span class="line">    msg = &apos;ok&apos;</span><br><span class="line">    erro_code = 0</span><br><span class="line">    </span><br><span class="line">class ServerError(APIException):</span><br><span class="line">    code = 500</span><br><span class="line">    msg  = &apos;sorry,we made a mistaake&apos;</span><br><span class="line">    erro_code = 999</span><br></pre></td></tr></table></figure></p>
<p>优化后视图函数<br>app\api\v1\client.py<br><figure class="highlight plain"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br><span class="line">16</span><br><span class="line">17</span><br><span class="line">18</span><br><span class="line">19</span><br><span class="line">20</span><br><span class="line">21</span><br><span class="line">22</span><br><span class="line">23</span><br><span class="line">24</span><br><span class="line">25</span><br><span class="line">26</span><br><span class="line">27</span><br><span class="line">28</span><br><span class="line">29</span><br><span class="line">30</span><br><span class="line">31</span><br><span class="line">32</span><br><span class="line">33</span><br><span class="line">34</span><br><span class="line">35</span><br><span class="line">36</span><br><span class="line">37</span><br><span class="line">38</span><br><span class="line">39</span><br><span class="line">40</span><br><span class="line">41</span><br><span class="line">42</span><br><span class="line">43</span><br><span class="line">44</span><br><span class="line">45</span><br><span class="line">46</span><br><span class="line">47</span><br><span class="line">48</span><br><span class="line">49</span><br><span class="line">50</span><br><span class="line">51</span><br><span class="line">52</span><br><span class="line">53</span><br></pre></td><td class="code"><pre><span class="line"></span><br><span class="line">from app.libs.redprint import Redprint</span><br><span class="line"></span><br><span class="line">from app.validators.forms import ClientForm,UserEmailForm</span><br><span class="line"># from flask import request  #  转移到Baseform中去了</span><br><span class="line">from app.libs.enums import ClientTypeEnum</span><br><span class="line">from app.models.user import User</span><br><span class="line"></span><br><span class="line"></span><br><span class="line"># from werkzeug.exceptions import HTTPException   #  异常</span><br><span class="line">from app.libs.erro_code import ClientTypeErro, ParameterException ,Success    # 导入自定义异常</span><br><span class="line"></span><br><span class="line">api = Redprint(&apos;client&apos;)  # 实例化一个Redprint</span><br><span class="line"></span><br><span class="line">@api.route(&apos;/register&apos;, methods = [&apos;POST&apos;] )  # 路由注册  # 因为这里把POST打成PSOT，导致不能使用POST访问，状态码405</span><br><span class="line">def create_client():                         </span><br><span class="line">    # 表单 - 一般网页  json - 一般移动端</span><br><span class="line">    # 注册 登录</span><br><span class="line">    # 参数 校验  接收参数</span><br><span class="line">    # WTForms 验证表单</span><br><span class="line"></span><br><span class="line">#用来接收json类型的参数</span><br><span class="line">    # data = request.json</span><br><span class="line"># 关键字参数data是wtform中用来接收json参数的方法</span><br><span class="line">    # form = ClientForm(data = data)  # data =   来接收json</span><br><span class="line">    # form = ClientForm()   # 转移到 BaseForm 中</span><br><span class="line"></span><br><span class="line">    # form.validate_for_api()</span><br><span class="line">    form = ClientForm().validate_for_api()</span><br><span class="line"># 替代switchcase-&#123;Enum_name:handle_func&#125;</span><br><span class="line">    promise = &#123;</span><br><span class="line">            ClientTypeEnum.USER_EMAIL: __register_user_by_email#,</span><br><span class="line">            # ClientTypeEnum.USER_MINA: __register_user_by_MINA   # 可在此处构建多种枚举类型</span><br><span class="line">        &#125;</span><br><span class="line">    promise[form.type.data]()</span><br><span class="line"></span><br><span class="line">    return Success()  #  将成功返回也当作一中 APIException</span><br><span class="line">#总 ↑</span><br><span class="line"></span><br><span class="line">#分 ↓</span><br><span class="line"></span><br><span class="line">def __register_user_by_email():</span><br><span class="line">#     form = UserEmailForm()</span><br><span class="line"># # if form.validate():</span><br><span class="line">#     form.validate_for_api() </span><br><span class="line">    form = UserEmailForm().validate_for_api()   # 为什么有括号</span><br><span class="line">    User.register_by_email(form.nickname.data,</span><br><span class="line">                               form.account.data,</span><br><span class="line">                               form.secret.data)</span><br><span class="line"></span><br><span class="line"></span><br><span class="line"># def __register_user_by_MINA():</span><br><span class="line">#     pass</span><br></pre></td></tr></table></figure></p>
<p>我们可以接受定义时候的复杂，但是不能够接受调用的时候复杂</p>
<p>定义是一次性的，但是调用是多次的，如果调用太过于复杂，会使得我们的 代码太过于臃肿</p>
<h1 id="4-2-全局异常处理"><a href="#4-2-全局异常处理" class="headerlink" title="4.2 全局异常处理"></a>4.2 全局异常处理</h1><p>当系统抛出不是我们自己定义的APIException的时候，返回的结果仍然会变成一个HTML文本。</p>
<p>我们在写代码的过程中，有那么类型的异常： 1.已知异常：我们可以预知的。如枚举转换的时候抛出的异常，这时候我们就会提前使用try-except进行处理。也可以抛出APIException 2.未知异常：完全没有预料到的。会由框架抛出的内置异常</p>
<p>我们可以使用flask给我们提供的处理全局异常的装饰器，采用AOP的设计思想，捕捉所有类型的异常。<br><figure class="highlight plain"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br><span class="line">16</span><br><span class="line">17</span><br><span class="line">18</span><br><span class="line">19</span><br><span class="line">20</span><br><span class="line">21</span><br><span class="line">22</span><br><span class="line">23</span><br><span class="line">24</span><br><span class="line">25</span><br><span class="line">26</span><br></pre></td><td class="code"><pre><span class="line">from app import create_app</span><br><span class="line">from app.libs.erro_code import ServerError</span><br><span class="line">from app.libs.erro import APIException</span><br><span class="line">from werkzeug.exceptions import HTTPException</span><br><span class="line"></span><br><span class="line">app = create_app()</span><br><span class="line"></span><br><span class="line">@app.errorhandler(Exception)  # python 基类的异常,因为我们要捕捉所有异常</span><br><span class="line">def framework_error(e):</span><br><span class="line">    if isinstance(e, APIException):</span><br><span class="line">        return e</span><br><span class="line">    if isinstance(e, HTTPException):  # 转化成APIException</span><br><span class="line">        code = e.code</span><br><span class="line">        msg = e.description</span><br><span class="line">        error_code = 1007</span><br><span class="line">        return APIException(msg, code, error_code)</span><br><span class="line">    else:</span><br><span class="line">        if not app.config[&apos;DEBUG&apos;]: # 判断是否在调试模式,不再,直接返回</span><br><span class="line">            return ServerError()</span><br><span class="line">        else:</span><br><span class="line">            raise e </span><br><span class="line">        return ServerError()</span><br><span class="line"></span><br><span class="line"></span><br><span class="line">if __name__ == &apos;__main__&apos;:</span><br><span class="line">    app.run(debug=True)</span><br></pre></td></tr></table></figure></p>

      
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              <div class="post-toc-content"><ol class="nav"><li class="nav-item nav-level-1"><a class="nav-link" href="#4-1-重写WTForms"><span class="nav-number">1.</span> <span class="nav-text">4.1 重写WTForms</span></a><ol class="nav-child"><li class="nav-item nav-level-3"><a class="nav-link" href="#优化1"><span class="nav-number">1.0.1.</span> <span class="nav-text">优化1</span></a></li></ol></li><li class="nav-item nav-level-2"><a class="nav-link" href="#思路"><span class="nav-number">1.1.</span> <span class="nav-text">思路</span></a><ol class="nav-child"><li class="nav-item nav-level-3"><a class="nav-link" href="#优化2"><span class="nav-number">1.1.1.</span> <span class="nav-text">优化2</span></a></li><li class="nav-item nav-level-3"><a class="nav-link" href="#优化3"><span class="nav-number">1.1.2.</span> <span class="nav-text">优化3</span></a></li><li class="nav-item nav-level-3"><a class="nav-link" href="#优化4"><span class="nav-number">1.1.3.</span> <span class="nav-text">优化4</span></a></li></ol></li></ol><li class="nav-item nav-level-1"><a class="nav-link" href="#4-2-全局异常处理"><span class="nav-number">2.</span> <span class="nav-text">4.2 全局异常处理</span></a></li></div>
            

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  <script type="text/javascript">
    // Popup Window;
    var isfetched = false;
    var isXml = true;
    // Search DB path;
    var search_path = "search.xml";
    if (search_path.length === 0) {
      search_path = "search.xml";
    } else if (/json$/i.test(search_path)) {
      isXml = false;
    }
    var path = "/" + search_path;
    // monitor main search box;

    var onPopupClose = function (e) {
      $('.popup').hide();
      $('#local-search-input').val('');
      $('.search-result-list').remove();
      $('#no-result').remove();
      $(".local-search-pop-overlay").remove();
      $('body').css('overflow', '');
    }

    function proceedsearch() {
      $("body")
        .append('<div class="search-popup-overlay local-search-pop-overlay"></div>')
        .css('overflow', 'hidden');
      $('.search-popup-overlay').click(onPopupClose);
      $('.popup').toggle();
      var $localSearchInput = $('#local-search-input');
      $localSearchInput.attr("autocapitalize", "none");
      $localSearchInput.attr("autocorrect", "off");
      $localSearchInput.focus();
    }

    // search function;
    var searchFunc = function(path, search_id, content_id) {
      'use strict';

      // start loading animation
      $("body")
        .append('<div class="search-popup-overlay local-search-pop-overlay">' +
          '<div id="search-loading-icon">' +
          '<i class="fa fa-spinner fa-pulse fa-5x fa-fw"></i>' +
          '</div>' +
          '</div>')
        .css('overflow', 'hidden');
      $("#search-loading-icon").css('margin', '20% auto 0 auto').css('text-align', 'center');

      $.ajax({
        url: path,
        dataType: isXml ? "xml" : "json",
        async: true,
        success: function(res) {
          // get the contents from search data
          isfetched = true;
          $('.popup').detach().appendTo('.header-inner');
          var datas = isXml ? $("entry", res).map(function() {
            return {
              title: $("title", this).text(),
              content: $("content",this).text(),
              url: $("url" , this).text()
            };
          }).get() : res;
          var input = document.getElementById(search_id);
          var resultContent = document.getElementById(content_id);
          var inputEventFunction = function() {
            var searchText = input.value.trim().toLowerCase();
            var keywords = searchText.split(/[\s\-]+/);
            if (keywords.length > 1) {
              keywords.push(searchText);
            }
            var resultItems = [];
            if (searchText.length > 0) {
              // perform local searching
              datas.forEach(function(data) {
                var isMatch = false;
                var hitCount = 0;
                var searchTextCount = 0;
                var title = data.title.trim();
                var titleInLowerCase = title.toLowerCase();
                var content = data.content.trim().replace(/<[^>]+>/g,"");
                var contentInLowerCase = content.toLowerCase();
                var articleUrl = decodeURIComponent(data.url);
                var indexOfTitle = [];
                var indexOfContent = [];
                // only match articles with not empty titles
                if(title != '') {
                  keywords.forEach(function(keyword) {
                    function getIndexByWord(word, text, caseSensitive) {
                      var wordLen = word.length;
                      if (wordLen === 0) {
                        return [];
                      }
                      var startPosition = 0, position = [], index = [];
                      if (!caseSensitive) {
                        text = text.toLowerCase();
                        word = word.toLowerCase();
                      }
                      while ((position = text.indexOf(word, startPosition)) > -1) {
                        index.push({position: position, word: word});
                        startPosition = position + wordLen;
                      }
                      return index;
                    }

                    indexOfTitle = indexOfTitle.concat(getIndexByWord(keyword, titleInLowerCase, false));
                    indexOfContent = indexOfContent.concat(getIndexByWord(keyword, contentInLowerCase, false));
                  });
                  if (indexOfTitle.length > 0 || indexOfContent.length > 0) {
                    isMatch = true;
                    hitCount = indexOfTitle.length + indexOfContent.length;
                  }
                }

                // show search results

                if (isMatch) {
                  // sort index by position of keyword

                  [indexOfTitle, indexOfContent].forEach(function (index) {
                    index.sort(function (itemLeft, itemRight) {
                      if (itemRight.position !== itemLeft.position) {
                        return itemRight.position - itemLeft.position;
                      } else {
                        return itemLeft.word.length - itemRight.word.length;
                      }
                    });
                  });

                  // merge hits into slices

                  function mergeIntoSlice(text, start, end, index) {
                    var item = index[index.length - 1];
                    var position = item.position;
                    var word = item.word;
                    var hits = [];
                    var searchTextCountInSlice = 0;
                    while (position + word.length <= end && index.length != 0) {
                      if (word === searchText) {
                        searchTextCountInSlice++;
                      }
                      hits.push({position: position, length: word.length});
                      var wordEnd = position + word.length;

                      // move to next position of hit

                      index.pop();
                      while (index.length != 0) {
                        item = index[index.length - 1];
                        position = item.position;
                        word = item.word;
                        if (wordEnd > position) {
                          index.pop();
                        } else {
                          break;
                        }
                      }
                    }
                    searchTextCount += searchTextCountInSlice;
                    return {
                      hits: hits,
                      start: start,
                      end: end,
                      searchTextCount: searchTextCountInSlice
                    };
                  }

                  var slicesOfTitle = [];
                  if (indexOfTitle.length != 0) {
                    slicesOfTitle.push(mergeIntoSlice(title, 0, title.length, indexOfTitle));
                  }

                  var slicesOfContent = [];
                  while (indexOfContent.length != 0) {
                    var item = indexOfContent[indexOfContent.length - 1];
                    var position = item.position;
                    var word = item.word;
                    // cut out 100 characters
                    var start = position - 20;
                    var end = position + 80;
                    if(start < 0){
                      start = 0;
                    }
                    if (end < position + word.length) {
                      end = position + word.length;
                    }
                    if(end > content.length){
                      end = content.length;
                    }
                    slicesOfContent.push(mergeIntoSlice(content, start, end, indexOfContent));
                  }

                  // sort slices in content by search text's count and hits' count

                  slicesOfContent.sort(function (sliceLeft, sliceRight) {
                    if (sliceLeft.searchTextCount !== sliceRight.searchTextCount) {
                      return sliceRight.searchTextCount - sliceLeft.searchTextCount;
                    } else if (sliceLeft.hits.length !== sliceRight.hits.length) {
                      return sliceRight.hits.length - sliceLeft.hits.length;
                    } else {
                      return sliceLeft.start - sliceRight.start;
                    }
                  });

                  // select top N slices in content

                  var upperBound = parseInt('1');
                  if (upperBound >= 0) {
                    slicesOfContent = slicesOfContent.slice(0, upperBound);
                  }

                  // highlight title and content

                  function highlightKeyword(text, slice) {
                    var result = '';
                    var prevEnd = slice.start;
                    slice.hits.forEach(function (hit) {
                      result += text.substring(prevEnd, hit.position);
                      var end = hit.position + hit.length;
                      result += '<b class="search-keyword">' + text.substring(hit.position, end) + '</b>';
                      prevEnd = end;
                    });
                    result += text.substring(prevEnd, slice.end);
                    return result;
                  }

                  var resultItem = '';

                  if (slicesOfTitle.length != 0) {
                    resultItem += "<li><a href='" + articleUrl + "' class='search-result-title'>" + highlightKeyword(title, slicesOfTitle[0]) + "</a>";
                  } else {
                    resultItem += "<li><a href='" + articleUrl + "' class='search-result-title'>" + title + "</a>";
                  }

                  slicesOfContent.forEach(function (slice) {
                    resultItem += "<a href='" + articleUrl + "'>" +
                      "<p class=\"search-result\">" + highlightKeyword(content, slice) +
                      "...</p>" + "</a>";
                  });

                  resultItem += "</li>";
                  resultItems.push({
                    item: resultItem,
                    searchTextCount: searchTextCount,
                    hitCount: hitCount,
                    id: resultItems.length
                  });
                }
              })
            };
            if (keywords.length === 1 && keywords[0] === "") {
              resultContent.innerHTML = '<div id="no-result"><i class="fa fa-search fa-5x" /></div>'
            } else if (resultItems.length === 0) {
              resultContent.innerHTML = '<div id="no-result"><i class="fa fa-frown-o fa-5x" /></div>'
            } else {
              resultItems.sort(function (resultLeft, resultRight) {
                if (resultLeft.searchTextCount !== resultRight.searchTextCount) {
                  return resultRight.searchTextCount - resultLeft.searchTextCount;
                } else if (resultLeft.hitCount !== resultRight.hitCount) {
                  return resultRight.hitCount - resultLeft.hitCount;
                } else {
                  return resultRight.id - resultLeft.id;
                }
              });
              var searchResultList = '<ul class=\"search-result-list\">';
              resultItems.forEach(function (result) {
                searchResultList += result.item;
              })
              searchResultList += "</ul>";
              resultContent.innerHTML = searchResultList;
            }
          }

          if ('auto' === 'auto') {
            input.addEventListener('input', inputEventFunction);
          } else {
            $('.search-icon').click(inputEventFunction);
            input.addEventListener('keypress', function (event) {
              if (event.keyCode === 13) {
                inputEventFunction();
              }
            });
          }

          // remove loading animation
          $(".local-search-pop-overlay").remove();
          $('body').css('overflow', '');

          proceedsearch();
        }
      });
    }

    // handle and trigger popup window;
    $('.popup-trigger').click(function(e) {
      e.stopPropagation();
      if (isfetched === false) {
        searchFunc(path, 'local-search-input', 'local-search-result');
      } else {
        proceedsearch();
      };
    });

    $('.popup-btn-close').click(onPopupClose);
    $('.popup').click(function(e){
      e.stopPropagation();
    });
    $(document).on('keyup', function (event) {
      var shouldDismissSearchPopup = event.which === 27 &&
        $('.search-popup').is(':visible');
      if (shouldDismissSearchPopup) {
        onPopupClose();
      }
    });
  </script>





  

  

  
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